JP2879638B2 - Forming method for metal strips with long grooves - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a long grooved metal strip used for electronic parts such as a lead frame of a power transistor and precision machine parts.

[0002]

2. Description of the Related Art Conventionally, when forming a long grooved metal strip a having grooves b as shown in FIG. 1 used for a lead frame, for example, a predetermined width and a predetermined plate thickness of pure copper or a copper alloy are used. The long metal material c formed as described above is formed by passing between a pair of rolling rolls d and e as shown in FIG.
In this rolling, the elongation of the material in the width direction is not constant,
After cutting both side edges of the strip material a to a predetermined width with a slitter, the strip material is pressed and used for a lead frame or the like.

[0003]

When the width dimension is finished by cutting off both side edges of the strip a with the above-mentioned slitter, a residual strain is generated in the strip a by a slitter blade. In addition, there is a disadvantage that the material a is warped, the flatness is impaired, and precise press molding cannot be performed. In addition, it is difficult to accurately set the relative positional relationship between the slitter blade and the groove b. There was a drawback that accuracy was poor.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method which can solve the above-mentioned drawbacks and can simplify the manufacturing process of a long grooved metal strip having no residual strain and having accurate groove positions.

[0005]

In the present invention, there is provided a means for solving], which in a groove while <br/> passed in one direction by continuously elongated metallic material of a rectangular cross-section between a pair of rolling rolls, Nagashakumizo In the method of forming a metal strip with a groove, a recess corresponding to the finishing width of the metal strip with a long groove is formed on a rolling roll provided with a ridge forming the groove, and the protrusion is formed in the recess. In order to achieve the above-mentioned object, by providing a strip and regulating the elongation of the long metal material in the width direction on the inner surface of the concave portion when the groove is formed in the long metal material by a rolling roll. I made it.

[0006]

When a long material prepared at a predetermined width and a predetermined thickness passes between a pair of rolling rolls, a groove is formed in the long material. One of the rolling rolls has a long grooved metal. A concave portion corresponding to the finished width of the strip is formed, and a ridge for forming the groove is provided in the concave portion, so that the length that is extended in the width direction by the ridge when rolling is performed. The elongation of the shank material is limited by the inner wall surface of the concave portion. As a result, the width of the formed strip is accurate and the positional relationship with the groove is accurately finished, and there is no need to cut the strip with a slitter, so that no residual strain is generated in the strip.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
In FIG. 3, reference numeral 1 denotes a long material formed of pure copper, a copper alloy, permalloy, or the like with a predetermined width and a predetermined thickness in a rectangular cross section. Is formed into a long metal strip having grooves similar to those shown in FIG. On one rolling roll 2a, as shown in FIG. 4, a ridge 3 for forming a groove is provided, and the ridge 3 is provided inside a concave portion 4 formed on the rolling roll 2a. did.

When the long material 1 is rolled between the rolling rolls 2a and 2b, the material 1 extending in the width direction by the rolling as shown in FIG.
, The width of the formed long metal material is accurate, and the distances A and B from the groove 5 to the side edges are accurately finished. The number and shape of the grooves 5 are arbitrary.

[0009] The rolling rolls 2a and 2b having the above configuration have a width of 30 mm.
mm, a long piece of pure copper material 1 having a rectangular cross section with a thickness of 1.5 mm is passed therethrough, two grooves 5 having a width of 1 mm and a depth of 1 mm are formed, and a distance A = 32 mm, a thickness of 1.3 mm and B = 1
When finished to 0.5 mm, | AB | <0.05,
The width of the strip was also in the range of 32 ± 0.1. In this case, the depth Tr of the roll roll recess 4 was set to be smaller than the predetermined plate thickness 1.3 mm and larger than 0.65 mm.
The lead frame was formed by press-molding the metal strip with a long groove. However, since there was no residual distortion, it was possible to press accurately without warping at the time of pressing.

[0010]

As described above, according to the present invention, a long metal material having a rectangular cross section is continuously placed between a pair of rolling rolls.
When forming a long grooved metal strip having a groove therein while passing in the direction, a concave portion corresponding to a finish width of the long grooved metal strip is formed on a rolling roll provided with a ridge forming the groove. Is formed, the protrusion is provided in the recess, and the elongation of the long material in the width direction due to the formation of the groove is regulated, so that the width dimension and the accuracy of the groove position of the formed strip are reduced. Since accurate roll forming can be performed and there is no need for processing such as slitting, there is an effect that the subsequent press forming without generating residual strain can be performed accurately.

[Brief description of the drawings]

FIG. 1 is a perspective view of a long grooved metal strip.

FIG. 2 is a cross-sectional view of a conventional molding method.

FIG. 3 is a side view of an embodiment of the present invention.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

[Explanation of symbols]

1 long metal material 2a, 2b rolling roll
3, 3 ridges 4 recesses 5 grooves

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B21H 8/00 B21B 1/08 B21B 27/02

Claims (2)

(57) [Claims] 1. A method of forming a groove in a long metal material having a rectangular cross section while continuously passing the metal material in a rectangular cross section in one direction between a pair of rolling rolls, and forming the metal material into a long grooved metal strip. A recess corresponding to the finishing width of the elongated grooved metal strip is formed in a rolling roll provided with a ridge forming the groove, and the ridge is provided in the recess, and the long strip is formed by a rolling roll. A method for forming a metal strip having a long groove, wherein when the groove is formed in a metal material, the elongation of the long metal material in the width direction is restricted on the inner surface of the concave portion. 2. The elongated member according to claim 1, wherein the depth of the concave portion is smaller than the thickness of the elongated metal material.
Forming method for grooved metal strip.